textproduct: Quad Cities

KEY MESSAGES

- Canadian wildfire smoke is forecast to spread across the area through tonight which will create hazy skies and poor air quality.

- Strong to severe storms are possible Monday and Monday night with potentially two rounds occurring. The Storm Prediction Center has an enhanced, level 3 out of 5, risk of severe storms along/north of I- 80. South of I-80 a slight, level 2 out of 5, risk for severe storms exist.

- Hot and humid conditions will be seen across the area on Monday. Peak heat indices on Monday will depend upon which storm scenario occurs. If there are no storms during the morning, then heat headlines would be needed for parts of the area.

SHORT TERM /THROUGH TONIGHT/

Issued at 149 AM CDT Sun Jul 19 2026

Slightly less humid conditions will be seen across the area today but dew points will begin climbing again tonight. Canadian wildfire smoke will create a hazy sky across the area with some minor visibility reductions

The question tonight is when rain could move back into the area. Dry conditions will be seen through midnight. After midnight the various short term models have been showing a gradual backing off on the potential for convection through sunrise. HOWEVER, internal signals suggest something moving into the northern parts of the area shortly after sunrise. Current data indicates that IF this scenario occurs it would be in a decaying phase. This makes sense since the LLJ would be rapidly decaying at this time.

LONG TERM /MONDAY THROUGH SATURDAY/

Issued at 149 AM CDT Sun Jul 19 2026

Monday/Monday night Assessment...medium (40-60%) confidence regarding heat headlines and strong to severe storm potential.

Two scenarios are in play for Monday.

Scenario 1: morning storms then evening severe storms

Nocturnal storms move into the area in a decaying mode bringing spotty rain to the area. Cloud cover from this convection helps suppress temperatures and thus delays the development of diurnal convection until close to sunset. The added cloud cover could keep peak heat indices in the 95 to 100 degree range.

Around sunset convection develops rapidly. Storms would initially be discrete and thus be capable of all severe hazards. However, storms would rapidly grow upscale into one or more organized bowing storm clusters.

Once the bowing storm clusters form, the potential for significant damaging winds (>75 mph) would become the main severe risk. Brief spin-up tornadoes in the bowing lines would also be possible.

Storms would be the most numerous during the evening hours but boundaries from these storms would then provide numerous foci for isolated to scattered storms that persist past midnight.

Scenario 2: a dry morning the severe storms developing mid to late afternoon.

The nocturnal storms remain across Minnesota and Wisconsin keeping the area dry. If this scenario occurs, the potential energy build-up in the atmosphere would set the stage for strong to severe storms to develop during the afternoon and continue into the evening hours. Additionally, this scenario would result in a heat headline.

Under this scenario, discrete storms would develop mid to late afternoon with all severe hazards possible. Like scenario 1, the discrete storms would rapidly grow upscale into one or more organized bowing storm clusters. Once this state occurs, the severe risk would transition to damaging winds being the primary risk. Brief spin-up tornadoes in the lines cannot be ruled out. Also like scenario 1, significant damaging winds (>75 mph) would be possible. Boundaries from these storms would provide numerous foci for additional storms to develop during the late evening with convection potentially ending after midnight.

Tuesday through Thursday Assessment...a certainty (>98%) of cooler and much less humid conditions after Tuesday

Tuesday will be dry as high pressure builds into the Midwest and the flow aloft turns to the northwest. Heat indices will range from the mid 80s to the low 90s due to lingering humidity until dew points drop Tuesday night.

Wednesday through Thursday look to be banner days; daytime highs 80 to 85 and low humidity levels.

Thursday night through Friday night Assessment...low (<25%) confidence regarding rain chances

Late Thursday night through Friday evening an upper level respectable upper level disturbance in the northwest flow will be paired with a weak surface low moving through Missouri.

The model consensus has 20-30% chances for rain centered mainly around late Thursday night and Friday morning. Given the northwest flow aloft across the area, moisture will be limited so it raises questions on how much rain could occur and what the real areal coverage of it will be.

The better moisture will run from the Plains into Missouri and there will be a frontal boundary associated with the low as it moves from Kansas across Missouri. I suspect the better rain chances will be along the frontal boundary across Missouri.

Saturday Assessment...a certainty (>95%) of humidity levels starting to rise

Return flow begins on Saturday as the heat dome builds north in the Plains. While not the overly humid conditions earlier in the week, dew points will start climbing into the low to mid 60s as temperatures climb above normal again.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Issued at 1219 AM CDT Sun Jul 19 2026

Cool front has moved into Missouri and southern Illinois. Northeast flow will slowly advect in smoke from wildfires which may create areas of MVFR visibilities along/east of the Mississippi that have the potential to persist through 00z/20. Winds of 10 knots or less will slowly become easterly after sunrise with an eventual southeast flow after 00z/20.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...Air Quality Alert until midnight CDT tonight for ILZ001-002- 007-009-015>018-024>026-034-035. MO...None.